Hello, it would be helpful if you can tell us what headphone or speakers that you want to use it with.
I think it’s not the smartest move to completely disregard the Ifi Zen DAC. There’s a difference between buying a product that happen to have MQA and buying a product just because it has MQA. If you really hate and allergic to MQA, just don’t choose the GTO filter firmware update.
IMO between the Zen DAC and the E30, the Zen DAC is still a better DAC. I think their Burrbrown chip implementation is quite good. The E30 has that digital glare if you will and if I’m going to be pedantic about it, their tonality is also not quite good.
For the Schiit stack, they’re quite good. The fact that they’re a stack also made it easier for future upgrades, but I’m quite concerned about their availability.
Between the Zen DAC and the Micca OriGen G2, I don’t really have any experience with the G2. So, I can’t really comment for it, but if you don’t plan to have a hard to drive headphone, the Zen DAC is a really good amp/DAC for its price. Hopefully it helps.
If you are interested, @WaveTheory made a review abt amps under $200.